Brush-holder for electric machines.



AM ZD" 1HE Namus PsTERs co.. wAsHlyaraN. n. r

GIORGIO FINZI AND EMILIO TALLERO, OF MILAN, ITALY.

BRUSH-HOLDER FOR ELECTRIC MACHINES.

Specification of Letters Patent.

Patented Dec. 24:, 1907.

Application filed April 2| 1906. SerialNo. 309,531.

To a77w7iom it may concern:

Be it known that we, GIORGIO FINZI and EMILIO TALLERO, subjects of the King of Italy, and residents of Milan, Italy, have invented certain new and useful Improvements in Brush-Holders for Electric Machines, of which the following is a specification.

The brush holders are one of the parts to which the makers of electric machines should pay the greatest attention. In most cases the same are bulky and do not admit of the total number of brushes on the commutator equalling the number of the poles, whereby both the carrying off of the current and the commutation are impaired, especially in as far as traction motors, etc., are concerned.

This invention aims at increasing the efflciency of the mechanical elements of the brush holders allowing of their being properly dimensioned, according to the rules of the art, in spite of their size, weight and cost being greatly reduced; their mounting and management are rendered moreover easy by the application of the invention in question. To this effect we provide on the side faces of the brush holder two springs with the corresponding pressing fingers, the arrangement of which is inversely symmetrical with reference to the two ends or terminal faces of the brush holder. The side face on the right hand will therefore for instance carry a spring and finger acting on the end and brush which are the nearest to the base, while the side face on the left hand carries a spring and finger acting on the end vand brush which are the farthest from the base. By this arrangement each of the two independent sets of springs and pressing -lingers may be made much longer than usually, whereby a much more perfect action is obtained than it would be the case, if said inversely symmetrical arrangement had not been resorted to.

In the drawings, Figure 1 is a front view and Fig. 2 a section of a brush holder in accordance with this invention.

The piece c is the brush holder proper, which is secured with an insulating intermediary to the. ring c7 or the machine frame. The pressing fingers c, e1 are pivoted on the centers f, f1 and acted u on bythe springs g, g1 secured to the fixe hooks t, il. The pressing fingers e, e1 are bent at their respective ends and carry springs 7L, 7L1 which are intended to exert their pressure on the carbon plates a and l) respectively.

The reference characters 71,2 71,3 denote respectively bearings for the springs 7i 7th Flexible leads 7c, 761 connected with the brush at one end and the brush holder at the other end prevent in the usual way the current from fiowing through and thereby heating the springs g, g1.

Though the drawing shows cylindrical helical springs, which best utilize the elasticity of the material, we do not limit ourselves to the employment of any special description of springs; nor does the invention contemplate the employment of two brushes only, the same being also applicable to three or a larger number of brushes, as what we claim is as follows:

1. A brush holder, a plurality of springs situated in planes containing the commutator axis and each of which is provided with a pressure finger having a portion thereof extending parallel to said axis, said fingers being alternately disposed with respect to each other and the point of attachment between one spring and a support being alternately disposed with respect to the point of attachment between the other spring and the support.

2. A brush holder comprising two independent systems of springs, and pressure ngers provided on the side faces of the brush holder and situated in planes containing the commutator axis and acting upon two different points of the brush.

3. A brush holder comprising two independent system of springs, pressure fingers provided on the side faces of the brush holder and situated in planes containing the commutator axis and acting upon two different points of the brush, and pivots for the pressure fingers, one of said pivots arranged near the base of the brush holder and commutator and the other pivot at a distance therefrom.

Signed at Milan this twenty-second day of March i906.

GIORGIO FINZI. EMILIO TALLERO. Witnesses:

B. CARLO SALvoTI, M. DE DRAGO. 

